铰接参数对跨活动断层隧道抗错断效果影响研究  

Influence of Flexible Joint Parameters on Anti-Fault Effect of Tunnel Across Active Fault

作　　者：陈花顺[1] CHEN Huashun(China Railway First Survey and Design Institute Group Co.,Ltd.,Xi'an 710043,China)

机构地区：[1]中铁第一勘察设计院集团有限公司,西安710043

出　　处：《铁道标准设计》2023年第12期156-162,共7页Railway Standard Design

基　　金：中铁第一勘察设计院集团有限公司科研项目(院科17-20)。

摘　　要：随着我国铁路建设的不断推进,山岭铁路隧道不可避免地会穿越活动断层区,而活动断层的错动会对隧道结构的安全性产生显著影响。为此,开展穿越断层隧道抗错断设计的相关研究具有重要的现实意义。铰接设计对跨活动断层区隧道衬砌的抗错断具有显著效果,为探究铰接参数对跨活动断层隧道抗错断效果的影响,以某铁路某跨走滑活动断层区隧道为背景,基于混凝土塑性损伤本构,建立三维弹塑性有限元模型。分析了断层错动时不同二衬节段长度、不同铰接缝宽度情况下二衬的损伤分布特征以及剪切应变大小。研究结果表明:百年最大错距30 cm作用下,无抗错断措施隧道二衬在错动面附近边墙处出现严重的受拉损伤,有贯通趋势,隧道拱顶与仰拱处产生严重的受压损伤,受压损伤因子有向两侧边墙贯通的趋势;铰接设计对隧道横向变形有较好的控制作用,可显著提升隧道的抗错断性能,且二衬节段长度越短,隧道抗错断效果越好,在隧道衬砌的铰接设计中,节段长度应不超过12 m;不同铰接缝宽度下隧道二衬的损伤情况基本一致,铰接缝宽度的变化对隧道抗错断效果并未产生明显影响,铰接设计中铰接缝宽度在满足要求的情况下应不大于0.3 m。With the continuous development of railway construction in China,mountain railway tunnels will inevitably pass through active fault areas,and the dislocation of active fault will have a significant impact on the safety of tunnel structure.Therefore,it is of great practical significance to carry out relevant research on anti-fault design of tunnel across fault.Articulated design has a significant effect on anti-fault resistance of tunnel lining across active fault area.In order to explore the influence of articulated parameters on anti-fault effect of tunnel lining across active fault area,a three-dimensional elastic-plastic finite element model was established based on concrete plastic damage constitutive model of a tunnel in a strike-slip active fault area of Sichuan-Tibet Railway.The damage distribution characteristics and shear strain of secondary lining with different length of segment and width of hinged joint were analyzed.The results show that under the maximum error distance of 30 cm in one hundred years,the second lining of tunnel without anti-fault measures has a serious tensile damage at the side wall near the fault surface,and has a tendency of transfixion,while the tunnel vault and invert have a serious compressive damage,and the compressive damage factors have a tendency of transfixion at both sides of the side wall.The articulated design has a good control effect on the transverse deformation of the tunnel,which can significantly improve the anti-fault performance of the tunnel.The shorter the length of the second lining segment,the better the anti-fault effect of the tunnel.In the articulated design of tunnel lining,the segment length should not exceed 12 m.The damage of the second lining of the tunnel is basically the same under different hinged joint widths.The change of the width of the hinged joint has no obvious influence on the anti-fault effect of the tunnel.The width of the hinged front in the hinged design should not be greater than 0.3 m when the requirements are met.

关 键 词：铁路隧道 走滑断层 铰接设计 断层错动 衬砌损伤 数值模拟 

分 类 号：U25[交通运输工程—道路与铁道工程] U459.1[建筑科学—桥梁与隧道工程]